Low profile marine air conditioner

ABSTRACT

A low profile, self-contained air conditioning unit for a nautical vehicle comprises a base pan, an air handler, a substantially horizontal compressor and a second heat exchanger. The air handler comprises a first heat exchanger with a medium conduit for channeling a refrigerating medium, an air moving apparatus within a shroud. The shroud includes a front wall having an air outlet and a rear wall having an air inlet and the first heat exchanger is located adjacent to the air inlet of the first wall. The second heat exchanger has an inner tube and an outer tube. The inner tube circulates water and the outer tube is in fluid communication with the medium conduit, coaxially encloses a substantial portion of the inner tube, and has an inlet and an outlet. The compressor and the second heat exchanger are adjacent to the air handler and the second heat exchanger is above the compressor.

FIELD OF THE INVENTION

The present invention relates to air conditioning systems and, more particularly, air conditioning systems on nautical vehicles.

BACKGROUND OF THE INVENTION

Providing air conditioning in vehicles of marine transportation is well known in the art. The installation of air conditioning systems on nautical vehicles must take into consideration the spatial limitations on board the ship. Generally, the dimensions of the components—a compressor, an evaporator, a condenser, an air handler, etc.—restrict the areas where air conditioning can be provided and certain areas of the ship will, as a result, benefit less from or have no benefit of air conditioning.

The size of a ship and space available on board generally will determine the type of air conditioning system used in a nautical vehicle. The larger chilled-water systems pump water around the boat from a central compressor through plumbing and air handlers installed in different areas of the boat blow air through water-channeling coils to provide heating or cooling. Direct-expansion systems differ in that they channel a refrigerant such as Freon instead of water. Self-contained units enable air conditioning in smaller-sized boats and do not require the remote transportation of the cooling medium because they package all the main components of the refrigeration cycle in one unit. Even for chilled-water or direct expansion air conditioning systems, in which air handlers are installed separately and at a distance from other larger components, the size of such air handlers will restrict their installation and the reach of the air conditioning will be limited. On-deck locations of a ship, such as a cockpit or a flybridge, are typical of areas where air conditioning is desired but difficult to provide due to spatial restrictions, for example, in terms of height, regardless of the type of air conditioning system used. Thus, there is a need to provide air conditioning in the limited on-deck space of a nautical vehicle without hampering its ordinary operations.

BRIEF SUMMARY OF THE INVENTION

In accordance with one aspect of the invention, a low profile, self-contained air conditioning unit for a nautical vehicle comprises a base pan, an air handler, a substantially horizontal compressor and a second heat exchanger. The air handler comprises a first heat exchanger with a medium conduit for channeling a refrigerating medium, an air moving apparatus, and a shroud housing the first heat exchanger and the air moving apparatus. The shroud includes a front wall having an air outlet and a rear wall having an air inlet and the first heat exchanger is located adjacent to the air inlet of the first wall. The second heat exchanger has an inner tube and an outer tube. The inner tube circulates water. The outer tube is in fluid communication with the medium conduit for channeling the refrigerating medium and coaxially encloses a substantial portion of the inner tube, and has an inlet and an outlet. The air handler and the compressor are mounted on the base pan. The compressor and the second heat exchanger are adjacent to the air handler and the second heat exchanger is above the compressor.

In accordance with another aspect of the invention, mounting of the air conditioning unit does not substantially decrease occupant space in the nautical vehicle.

In accordance with yet another aspect of the invention, the air conditioning unit does not exceed a height of 8 inches (203 mm).

In accordance with still another aspect of the invention, the air moving apparatus is a centrifugal fan and the rear wall of the shroud is parallel to the rotational axis of the air moving apparatus.

In accordance with still another aspect of the invention, a plurality of centrifugal fans is placed side-by-side in a coaxial manner.

In accordance with still another aspect of the invention, the plurality of fans is operated by a single motor.

In accordance with still another aspect of the invention, the self-contained air conditioning unit is connected via a duct to a supply air grill.

In accordance with still another aspect of the invention, the air inlet extends over substantially all of the rear wall.

In accordance with still another aspect of the invention, orientation of air from the air outlet is controlled by a plenum attachment.

In accordance with still another aspect of the invention, the first heat exchanger comprises the medium conduit passing through a set of parallel fins repeatedly thereby forming a bank of medium conduits.

In accordance with still another aspect of the invention, the self-contained air conditioning unit further includes a reversing valve and provides heating and cooling.

In accordance with still another aspect of the invention, an inlet of the inner tube is connected to a pump for circulating water.

In accordance with still another aspect of the invention, the inner tube circulates water from a body of water neighboring the nautical vehicle.

In accordance with still another aspect of the invention, the air conditioning unit can be installed at various height-critical locations of the nautical vehicle.

In accordance with still another aspect of the invention, an air handler for a nautical vehicle comprises a first heat exchanger, an air moving apparatus, and a shroud housing the first heat exchanger and the air moving apparatus. The first heat exchanger includes a medium conduit channeling a refrigerating medium and the medium conduit has a medium inlet and a medium outlet. The shroud includes a front wall containing an air outlet and a rear wall containing an air inlet. The first heat exchanger is located adjacent to the air inlet of the rear wall. The mounting of the air handler does not substantially decrease occupant space in the nautical vehicle.

In accordance with still another aspect of the invention, the air handler further comprises a base pan with a condensate drain.

In accordance with still another aspect of the invention, the air first heat exchanger is in fluid communication with a compressor and a second heat exchanger that are not adjacent to the air handler and the air handler is part of a centralized air conditioning system.

In accordance with still another aspect of the invention, the refrigerating medium is water and the air handler is part of a chilled-water air conditioning system.

In accordance with still another aspect of the invention, the refrigerating medium is a refrigerant and the air handler is part of a direct expansion air conditioning system.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a front perspective view of an air handler in a self-contained air conditioning unit in accordance with a first example embodiment of the invention.

FIG. 2 is a rear perspective view of the air handler in the self-contained air conditioning unit in accordance with a first example embodiment of the invention.

FIG. 3 is a rear plan view of the air handler in the self-contained air conditioning unit in accordance with a first example embodiment of the invention.

FIG. 4 is a top schematic view of the interior of the air handler in the self-contained air conditioning unit and the air flow therein.

FIG. 5 is a front plan schematic view of the first heat exchanger.

FIG. 6 is a cross sectional side schematic view of the interior of the air handler and the air flow therein.

FIGS. 7A and 7B are cross sectional views of the water conduit and the heat exchange therein.

FIG. 8 is a top perspective view of the air handler in accordance with a second example embodiment of the invention.

FIG. 9 is a top perspective view of the air handler in accordance with a third example embodiment of the invention.

FIGS. 10A and 10B are views of example installations of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Air conditioning is defined as the treatment of air for the purpose of heating, cooling or ventilating air and an air conditioning system or unit is any application which is used for such a purpose. HVAC which stands for heating, ventilating and air conditioning is an industry term that is synonymous with air conditioning. The terms “air conditioner” or “air conditioning” will be used to encompass any treatment of air including heating and cooling and may include heat pump but also other HVAC devices. Air conditioning is also meant to encompass both indoor air conditioning, which is limited to the air conditioning of an enclosed area and outdoor air conditioning, which occurs in the open air.

Depending on the type of air conditioning system, the refrigerating medium can be a fluorinated hydrocarbon such as Freon in case of a direct expansion air conditioning system or water in case of a chilled water air conditioning system.

FIGS. 1-4 show an embodiment of a self-contained air conditioning unit 40 in which the main components of a refrigerating cycle are present. The main components, which are mounted on a base pan 18, are a compressor 11, a first heat exchanger 12 (shown in FIG. 4) located inside an air handler 10 and a second heat exchanger 17.

The compressor 11 is a rotary compressor that is mounted on a pedestal 21 built on the floor of the base pan 18 and is in a substantially horizontal position contributing to the low profile of the air conditioning system. A substantially horizontal position refers to the position of a longitudinal axis of the compressor. The compressor 11 can be of any commercially available type that is suitable for the dimensions intended by a manufacturer. A basal portion of the compressor 11 may be secured onto the base pan 18 using, for example, a mounting bolt, a grommet and a fastening means such as a nut or a cotter pin. A medium conduit 30 channels the refrigerating medium from the compressor 11 to a reversing valve 19 which routes the refrigerating medium to one of the two heat exchangers 12, 17 depending on the air conditioning mode. In a heating mode, the reversing valve 19 will channel the refrigerating medium to the first heat exchanger 12, while in a cooling mode, the reversing valve 19 will channel the refrigerating medium to the second heat exchanger 17.

In this embodiment of a self-contained unit 40, the second heat exchanger 17 is located above the compressor 11 and is held in place by a number of vertical beams 23 that are fastened to the base pan 18 through securing means such as screws and provide a support in the form of a stairway step on which the second heat exchanger 17 can rest. The second heat exchanger 17 has a tube-in-tube structure in which the medium conduit 30 is in fluid communication with the outer tube 46 and in which a water conduit 44 is the inner tube 45 as shown in FIGS. 7A and 7B. The water conduit 44 has a water inlet 48 and a water outlet 50 and curls in a series of rectangular loops above the compressor 11. A substantial portion of the inner tube 45 is coaxially enclosed within the outer tube 46 as shown in FIG. 7A and the heat exchange takes place between the refrigerating medium and water 51 across the walls of the medium conduit 30 throughout the tube-in-tube structure as shown in FIG. 7B. A person of ordinary skill in the art will understand that the direction of heat transfer is arbitrarily drawn in FIG. 7B and that, in reality, heat transfer is possible in the opposite direction as well because heat will be transferred from refrigerating medium in the outer tube 46 to the water 51 in the inner tube 45 when the second heat exchanger 17 operates as a condenser in the refrigerating cycle while heat will be transferred from the water 51 in the inner tube 45 to the refrigerating medium in the outer tube 46 when the second heat exchanger 17 operates as an evaporator in the refrigerating cycle. The directions of the flow of the water 51 and the refrigerating medium are also arbitrarily drawn in FIG. 7B. While the direction of the flow of water 51 is constant, the direction of the refrigerating medium will either be in the same or opposite direction depending on the desired mode of air conditioning. Water 51 flowing through the water conduit 44 is drawn by a pump (not shown) from a body of water 80 neighboring a nautical vehicle 1 in which the self-contained air conditioning unit 40 could be installed. The inner tube 45 and outer tube 46 are composed of alloys chosen based on factors such as thermal conductivity and corrosion resistance to sea water while this example embodiment uses cupronickel tubes. It is to be noted that the present invention is not limited to use at sea.

While one end of the medium conduit 30 is routed to enter the water conduit 44 from the reversing valve 19, the other end of the medium conduit 30 that exits the water conduit 44 is routed through an expansion valve/capillary tube 19 and then to the first heat exchanger 12 located inside the air handler 10.

For embodiments of the self-contained unit 40, it is to be appreciated that different arrangement of the compressor 11 and the second heat exchanger 17 is possible while maintaining a similar height for the combined structure. For example, the compressor 11 could be stacked above the second heat exchanger 17 or the water conduit 44 of the second heat exchanger 17 could surround the compressor 11 to achieve an even lower profile.

FIGS. 1-3 show an embodiment of the air handler 10 as a box-shaped shroud 20 with an air inlet 26 on a rear wall 22 and air outlets 28 a and 28 b on a front wall 24, opposite the rear wall 22. The shroud 20 houses two fans 14 a and 14 b, a motor 16 and the first heat exchanger 12. The embodiment in FIG. 4 shows the first heat exchanger 12 located adjacent to the air inlet 26 and inside the shroud 20. The effect of such an arrangement is that any air entering the air inlet 26 will undergo heat exchange immediately at entry.

FIG. 5 shows a schematic view of an embodiment of the first heat exchanger 12 detached from the shroud 20. The first heat exchanger 12 is made up of the medium conduit 30 and a set of parallel fins 13. The medium conduit 30 passes through a set of parallel fins 13 that are arranged so as to cut across the conduit 30 and the conduit 30 is bent to pass through the set of fins 13 multiple times. Such an arrangement of the conduit 30 extends across the length of the rear wall 22 and the portions of the conduit 30 that are bent protrude to the exterior of the shroud 20 as shown in FIG. 3. In FIG. 6 where a cross section of the shroud 20 is shown, the air entering through the air inlet 26 must pass through the bank of conduits 30 formed by the first heat exchanger 12 and is directed out of the shroud 20 to the air outlets 28 a and 28 b through the fans 14 a and 14 b. The degree of heat exchange in the first heat exchanger 12 is proportional to the number of rows of the medium conduit 30 extending across the air inlet 26 because each row of medium conduit 30 contributes to heat exchange between the air and the refrigerating medium. A person of ordinary skill in the art will appreciate that the arrangement of medium conduit 30 is not limited to the embodiment shown in FIG. 5 where the path of the conduit 30 is substantially in the same plane and that various alternative arrangements will achieve differing efficiencies in heat exchange.

Referring to FIGS. 4 and 6, air flow caused by fans 14 a and 14 b are shown. The fans 14 a and 14 b can be of any type as long as they direct air to the air outlets 28 a and 28 b. Centrifugal fans may be operated by a conventional electric motor 16 located between the fans 14 a and 14 b as shown in this embodiment. In such an embodiment, the centrifugal fans are placed side-by-side and their axis of rotation are coaxial. By using two, side-by-side fans, this embodiment eliminates the need for a transition box which would be necessary if a single air moving apparatus were used. A person of ordinary skill in the art will appreciate that other air moving apparatus such as axial fans would also be suitable, that the number of air moving apparatuses inside the air handler 10 is a matter of choice and that the arrangement of the air moving apparatuses or the arrangement of the air motor 16 relative to the air moving apparatus can vary and achieve differing effects. As shown in FIG. 6, the centrifugal fans are oriented so that the rotational axis is parallel to the rear wall 22 and the air will travel across the width of the air handler 10 from the rear wall 22 to the second wall 24. The air discharged from the air outlets 28 a and 28 b can ducted to supply air grilles (not shown) that provide air conditioning to a designated area or can be redirected using a plenum attachment (not shown). Ideally, the air inlet 26 will take up substantially all of the surface of the rear wall 22 so that a maximum amount of opening is provided for air to be taken in for heat exchange. The air inlet 26 can be an opening that is part of the body of the shroud 20 made by processing the rear wall 22 directly or can be a grating of metal or other material assembled onto the rear wall 22 thus covering up the inlet 26. An air filter could be mounted so that the air intake is cleaned of contaminants before being drawn through the heat exchanger 12 and the fans 14 a and 14 b.

Because the medium conduit 30 of the first heat exchanger 12 must be routed to be in communication with the other components of the refrigerating cycle, the installation of the motor, the first heat exchanger 12 and the fans 14 a, 14 b and the routing of the medium conduit 30 are likely to precede the mounting of the shroud 20. The shroud may consist of a number of substantially planar surfaces that can be assembled and fastened onto one another and the base pan 18 via brackets with holes for accepting screws. Moreover, the planar surfaces can be made of metal or other rigid material resistant to heat, cold and moisture. A person of ordinary skill in the art will appreciate that the shroud 20 can take on shapes other than a box, that the assembly of the shroud can be simplified through means that allow for assembly of the planar surfaces prior to mounting onto the base pan 18 and that the shroud 20 need not consist of planar surfaces only.

As shown in FIGS. 2-3, the base pan 18 can also include drain openings to allow condensate drains 38 a, 38 b, 38 c to be fitted onto the based pan 18 in order to remove any condensation formed on the medium conduit 30 by the phase change of the refrigerating medium. Condensate drains 38 a, 38 b, 38 c which connect to drain lines may be made up of at least a drain fitting, a washer and a locking nut. The base pan 18 may be inclined so as to channel any liquid build up toward the condensate drains 38 a, 38 b, 38 c. Moreover, the base pan 18 will be made of corrosion-resistant metal such as stainless-steel.

FIG. 8 shows an embodiment of the air handler 60 for a chilled-water air conditioning system. In a chilled-water air conditioning system, the refrigerating medium is water and a centralized system in which all the other components of a refrigerating cycle are located circulates water to air handlers 10 installed in different parts of a nautical vehicle 1. The air handler 60 has a medium inlet 34 to accept the incoming refrigerating medium from the centralized pump and a medium outlet 36 to discharge it.

FIG. 9 shows an embodiment of the air handler 70 for a direct expansion air conditioning system which also has remotely located components but uses a refrigerant as the refrigerating medium. FIG. 9 shows the type of medium inlet 34 and medium outlet 36 used in the air handler 70. The medium inlet 34 and the medium outlet 36 are also respectively known as a flare suction and a flare discharge.

As explained above, when the self-contained unit 40 is put to operation, the first heat exchanger 12 and the second heat exchanger 17 can interchangeably perform the dual role of an evaporator and a condenser depending on the air conditioning mode. The term ‘heat exchanger’ is used instead of ‘condenser’ and ‘evaporator’ to indicate these dual functions. A medium conduit 30 channels the refrigerating medium through the major components of the air conditioning system starting from the compressor 11 then through the reversing valve 19, one of the two heat exchangers, an expansion valve/capillary tube 25, the other heat exchanger and back to the compressor 11.

The main advantage of this invention is that the compactness of the components enables the installation of air conditioning equipments in areas of a nautical vehicle where space for mounting air conditioning equipments is limited and where conventional equipments would take up more than the available space. Mounting space can be seen as limited where a confined area does not provide much room or where an area, although not confined, does not offer much foundation on which to install air conditioning components. More specifically, the present invention may be installed adjacent to spaces provided for an operator or passenger on the vehicle in a way that the body of the air conditioning unit or the air handler does not result in a substantial decrease in the room provided for the operator or passenger. For example, the present invention may simply take up some room behind a wall adjacent to the space provided for the operator because primarily the installation simply requires inserting the body of the air conditioning system behind the wall. The space may be a cockpit, an outdoor guest area, or an indoor room.

FIGS. 10A and 10B illustrate the benefits of the air handler 10 (or self-contained air conditioning unit 40). In FIGS. 10A and 10B, the present invention is installed in hollow spaces available within the existing structure of the nautical vehicle and does not interfere with the space provided for occupants, such as the guest area or the cockpit. In FIG. 10A, an indoor guest area 110 is shown. The conditioned air from the air handler 10 is channeled via ducts 100 to supply air grills 102 on surfaces 104 and provides heating or cooling. The ducts 100, similarly to the air handler 10, are found behind the surfaces 104 surrounding the guest area 110 and do not interfere with the space provided for occupants. The ducts 100 may be routed in various manners depending on space available behind the surfaces 104. The locations of the supply air grills 102 will also vary depending on the routes of the ducts 100, space on the surfaces 104 for placing the supply air grills 102 and the desired air conditioning effects. In FIG. 10B, a cockpit 120 is shown illustrating another example setting for the present invention and, in this embodiment, the supply air grills 102 are found below the dashboard. The installation of the ducts 100 and the air handler 10 does not decrease the space provided for the operator because they occupy space that is already available within the existing structure of nautical vehicle. The present invention can be implemented by varying the routes of ducts 100, the locations of supply air grills 102 and the location of the air handler 10. The compactness of the present invention provides a solution in situations where air conditioning units of conventional dimensions typically cannot be installed without substantially decreasing occupant space.

In this regard, the self-contained air conditioning unit 40 that has a height of less than 8 inches (or 203 mm) and length of less than 31 inches (or 789 mm) can be mounted despite the lack of mounting space. The invention thus enables air conditioning at on-deck locations such as a flybridge or cockpit in addition to enclosed areas such as a cabin where air conditioning is generally contemplated. The present invention enables installation of air conditioning equipments at a cockpit dashboard so that the pilot of the nautical vehicle can experience heating or cooling more effectively even in the open air.

Moreover, the availability of embodiments that can adapt with different types of air conditioning systems offers broad compatibility with pre-installed air conditioners in nautical vehicles. Embodiments of the self-contained air conditioning unit 40 form an air conditioning system that can function independently of a remote and centralized system. Therefore, self-contained air conditioning unit 40 can provide air conditioning in areas where conventional units could not be installed without any rewiring of medium conduit 30 of an existing air conditioning system. The air handlers 60 and 70 enable the blowing of heated or cooled air in a similar fashion whether the nautical vehicle 1 uses a chilled water or direct expansion air conditioning system.

Although the invention has been described in terms of a few example embodiments, the invention is not limited to the details of the discussed embodiments and a person of ordinary skill in the art will appreciate that various modifications can be made to the embodiments while staying within the scope and spirit of the appended claims. 

1. A low profile, self-contained air conditioning unit for a nautical vehicle, comprising: a base pan; an air handler comprising: a first heat exchanger with a medium conduit for channeling a refrigerating medium, an air moving apparatus, and a shroud housing the first heat exchanger and the air moving apparatus, the shroud including a front wall having an air outlet and a rear wall having an air inlet, the first heat exchanger located adjacent to the air inlet of the first wall; a substantially horizontal compressor, the air handler and the compressor mounted on the base pan; and a second heat exchanger having an inner tube and an outer tube, the inner tube circulating water, the outer tube being in fluid communication with the medium conduit for channeling the refrigerating medium, the outer tube coaxially enclosing a substantial portion of the inner tube, the outer tube having an inlet and an outlet, wherein the compressor and the second heat exchanger are adjacent to the air handler and the second heat exchanger is above the compressor.
 2. The self-contained air conditioning unit of claim 1, wherein mounting of the air conditioning unit does not substantially decrease occupant space in the nautical vehicle.
 3. The self-contained air conditioning unit of claim 1, wherein the air conditioning unit does not exceed a height of 8 inches (203 mm).
 4. The self-contained air conditioning unit of claim 1, wherein the air moving apparatus is a centrifugal fan and the rear wall of the shroud is parallel to the rotational axis of the air moving apparatus.
 5. The self-contained air conditioning unit of claim 4, wherein a plurality of centrifugal fans is placed side-by-side in a coaxial manner.
 6. The self-contained air conditioning unit of claim 5, wherein the plurality of fans is operated by a single motor.
 7. The self-contained air conditioning unit of claim 5, wherein the self-contained air conditioning unit is connected via a duct to a supply air grill.
 8. The self-contained air conditioning unit of claim 1, wherein the air inlet extends over substantially all of the rear wall.
 9. The self-contained air conditioning unit of claim 1, wherein orientation of air from the air outlet is controlled by a plenum attachment.
 10. The self-contained air conditioning unit of claim 1, wherein the first heat exchanger comprises the medium conduit passing through a set of parallel fins repeatedly thereby forming a bank of medium conduits.
 11. The self-contained air conditioning unit of claim 1, wherein the self-contained air conditioning unit further includes a reversing valve and provides heating and cooling.
 12. The self-contained air conditioning unit of claim 1, wherein an inlet of the inner tube is connected to a pump for circulating water.
 13. The self-contained air conditioning unit of claim 1, wherein the inner tube circulates water from a body of water neighboring the nautical vehicle.
 14. The self-contained air conditioning unit of claim 1, wherein the air conditioning unit can be installed at various height-critical locations of the nautical vehicle.
 15. An air handler for a nautical vehicle, comprising: a first heat exchanger including a medium conduit channeling a refrigerating medium, the medium conduit having a medium inlet and a medium outlet; an air moving apparatus; and a shroud housing the first heat exchanger and the air moving apparatus, the shroud including a front wall containing an air outlet and a rear wall containing an air inlet, the first heat exchanger located adjacent to the air inlet of the rear wall, wherein mounting of the air handler does not substantially decrease occupant space in the nautical vehicle.
 16. The air handler of claim 15, wherein the air handler further comprises a base pan with a condensate drain.
 17. The air handler of claim 15, wherein the air first heat exchanger is in fluid communication with a compressor and a second heat exchanger that are not adjacent to the air handler and wherein the air handler is part of a centralized air conditioning system.
 18. The air handler of claim 17, wherein the refrigerating medium is water and the air handler is part of a chilled-water air conditioning system.
 19. The air handler of claim 17, wherein the refrigerating medium is a refrigerant and the air handler is part of a direct expansion air conditioning system. 